Sheave construction for lever-arm buckets



-Ap 6, 1929. w. M. VENABLE SHEAVE CONSTRUCTION FOR LEVER ARM BUCKETSFiledJune 1925 2 Sheets-Sheet INVENTOR A r-mpnmvs April16, 1929.WMVENABLE 1,709,418.

SHEAVE CONSTRUCTION FOR LEVER ARM BUCKETS File J1me 1925 2 Sheets-Sheet2 INVENTOR' I TTORNEYs Patented Apr. 16,1929.

{U ITED STATES a 1,709,418 PATENT OFFICE. A

WILLIAM MAYO VENA'BLE, or rrr'rsmrnen, r'eNNsyL'vAnIA, AssiGNoR To BLAw-KNOX columnar, aoonronnrmnor'nnw JERSEY.

SHEAVE ooNs'm o'rioN Eon LEVER-ARM isucim rs.

Application filedJuneG, 1925. Serial 35,283. v

This invention relates to various improve} ments associated with thesheaves of a lever arm bucket and it has for its principal objects theprovision of arrangements forensuring greater dependability in operationof the bucket, longer life of the parts, better lubrication of movingsurfaces, more protection from grit and dirt, greater simplicity inmanufacture and assembly as well as in repair, etc.

In connection with the foregoing I wish to I also wish to point out thatin lever arm type of bucket there are generally two sheaves in the leverarm and, during operation of the bucket these sheaves are constantlybeing raised and lowered so that in the ahi use of the bucket would haveto be suspended until a cleaning operation had been effected.

Furthermore there are stretches of the operating cable on either sideofthe sheaves and care must be taken not to interfere with the free runof the cable. These matters have all then taken care of inmyimprovements as will appear. 7

It is further desired to point out that the space available forthevarious parts associated withthe lever arm of a bucket is very limitedand that mere increase in size is not permissible in order to securestrength and dent to my invention I obtainby means of a constructionwhich is illustrated in preferred form in the accompanying drawings,wherein bucket embodying my improvements with the bucket shown in openposition and i Fig. 2is an enlarged longitudinal section are stretchesof the cable oneach V sheaves. a

sence of suitable means for automatically maintaining the scores in aclean condition,

Fig. 1.is a side elevation'of a lever arm thru the lever arm sheave pininorder to illustrate various details of the invention.

Referring to the drawings it will be seen that the lever arm 1 of thebucket is-of forked construction at its outer endthe spaced members 2 ofwhich being adapted to carry between then the sheaves 3 and 4. i Abushingb -with integral end-closure plate 6 is mounted in a suitableopeningin each memberQ. Securing bolts 7 arranged c rcumferentiallyaround the pin pass through the flange 8 of ings 9gin'the members 2.

A sheave pin'lO, is mounted in the bushings and a sheave l is keyed-tothis pin so that the two parts rotatetogether, the sheaves t beingmounted, as shown, immediately, adjacent one of the bushings 5.

the cover plate into suitable threaded open- Between the sheave 4 andthe other bushing 5'is'mounted the other sheave lupon a rotatablebushlng llkeyed or otherwise secured to the sheave.

.The operating Cable 1 2 ,is reeve'd around the sheaves 1n theusualinanner so that there side ofthe In order to maintain clean scoresin the sheaves I secure'the strap 13 to the upstanding lugs 14 on'themembers 2 and upon this strap I mount a suitable cleaning tool 15 foreach sheave scorewhich, in the present instance, takes the shape of athreaded bolt passing down thru the strap asshownwi'th lock'nuts 16 tohold them in any desired position of adjustment. These tools arepreferably adjustable so as to come very close to the bottom of thesheave scores and they, 'to-,'

gether With-the lugs '14 and the strap 13 are so located betweenthestret'ches of-the cable 12 Y asnot to interfere in anywaywith theoperation of the bucket. Lubricationis accomplished in the followingmanner. A longitudinal hole or passage 17 is formed in each end of thepin 10 and this connects to thetransverse passages 18 arranged todischarge into the annular groove 19 in the bushing 5. Lubricant isforced in under pressure through the opening. occupied by the plug 20and after sufficient lubricant has been introduced itwill be seen thatthere is no outlet for it except 1 at the far or inner end of'thebushing be J tween the bushing and the sideof the adjacent sheave.By forcing anexcess" of lubricant through the bearing in-this manner itthe proper supply 01" lubricant is maintainedthere is practically noopportunity for dirt or grit to enter and score the bearing.

The bushing 11 is lubricated through a' passage 21 in the sheave hub thesheave 3. The passage 21 communicates through an opening; 23 Withtheannular groove 2%- on the inside of the bushingrlli It will be seen thatI have provided large adequate bearings for the pin 10. This makes itpossible to use a very small hub for the sheave 4: which rotates withthe pin and provides adequate space'for the large hub 22 of the sheave3. In this Way the sheave 3 has room for an ample bearing upon the pinthrough its bushing 11 and it will be noted that the bottoirrot thesheave score is approximately over the center of this bearing. In formerconstructions the sheave hubs abutted approximately along the line ofthe adjacent sheave flanges 26 so that v theload was not central overthe bearings,

As a consequence the bearings were more on the inside than they did onthe outside and caused a "\vobbling of the'sheaves so that their flanges26 rubbed together and rapidly were away. This difiiculty is completelyovercome by my improvedconstruction.

The usual reeving of the cable 12 causes a rotation of the sheaves 3ande 1n the same A greater speed than the other.

direction with one sheave travelling at a 7 It will be seen, therefore,that my improved arrangement reduces to a great degree the amount ofvWear incident to the rotation of the sheaves.

I claim I 1. In a lever arm bucket, the combination of a sheave in thearm, stretches of line on each side 01" the sheave, and a cleaning toolsupported from the arm and projecting between the stretches of said lineinto the score of the sheave. V V

2. In an excavating bucket,the combination of a sheave support, sheavemounted therein, stretches of line on each side oi the sheave, and acleaning tool carried bysaid support and projecting bet 'een thestretches of said line into the score of the sheave.

3 In a lever arm bucket, thecoinbination oil a sheave in thearm,'stretches of line on each side of the sheave, a support on thelever arm adjacent the sheave between the stretches of the line, and acleaning toolcarried by said support and projecting into the score'ofthe sheave.

4:. In a lever arm buc ret, the combination of a sheave in the arm,stretches of operating cable on each side of the sheave, a strap on thearm between the stretches and passing over the sheave, and cleaning toolprojecting from the strap into the score of the sheave v a In testimonywhereof, I have hereunto signed my name. 7

WILLIAM M. VENABLE

